09 2015 档案

[LeetCode] Find the Duplicate Number
摘要：There are mainly two solutions to solve this problem.The first one is very clever, using the idea of cycle detection, and runs in O(n) time. You may r... 阅读全文
posted @ 2015-09-28 17:26 jianchao-li 阅读(381) 评论(0) 推荐(0) 编辑
[LeetCode] Walls and Gates
摘要：Problem Description:You are given am x n2D grid initialized with these three possible values.-1- A wall or an obstacle.0- A gate.INF- Infinity means a... 阅读全文
posted @ 2015-09-24 20:57 jianchao-li 阅读(3899) 评论(0) 推荐(1) 编辑
[LeetCode] Inorder Successor in BST
摘要：Problem Description:Given a binary search tree and a node in it, find the in-order successor of that node in the BST.Note: If the given node has no in... 阅读全文
posted @ 2015-09-22 15:59 jianchao-li 阅读(3569) 评论(0) 推荐(0) 编辑
[LeetCode] Peeking Iterator
摘要：An interesting problem about iterators. This post shares a very nice solution, which is rewritten below, with minor simplifications.// Below is the in... 阅读全文
posted @ 2015-09-21 12:18 jianchao-li 阅读(386) 评论(0) 推荐(0) 编辑
[LeetCode] Expression Add Operators
摘要：This post shares a very nice solution, which is rewritten below. 1 class Solution { 2 public: 3 vector addOperators(string num, int target) { 4 ... 阅读全文
posted @ 2015-09-16 21:58 jianchao-li 阅读(465) 评论(0) 推荐(0) 编辑
[LeetCode] Zigzag Conversion
摘要：The key challenge to this problem is to make the code clean. This post has shared a nice example, which is rewritten below in C++.class Solution {publ... 阅读全文
posted @ 2015-09-14 14:53 jianchao-li 阅读(219) 评论(0) 推荐(0) 编辑
[LeetCode] Zigzag Iterator
摘要：Problem Description:Given two 1d vectors, implement an iterator to return their elements alternately.For example, given two 1d vectors:v1 = [1, 2]v2 =... 阅读全文
posted @ 2015-09-14 14:16 jianchao-li 阅读(2468) 评论(0) 推荐(0) 编辑
[LeetCode] Wiggle Sort
摘要：Problem Description:Given an unsorted arraynums, reorder itin-placesuch thatnums[0] = nums[2] = nums[i - 1];Ifiis even, thennums[i] & nums) {4 ... 阅读全文
posted @ 2015-09-10 12:57 jianchao-li 阅读(2465) 评论(0) 推荐(0) 编辑
[LeetCode] Perfect Squares
摘要：Well, after seeing the similar problems, you may have known how to solve this problem. Yeah, just to construct larger numbers from smaller numbers by ... 阅读全文
posted @ 2015-09-09 22:47 jianchao-li 阅读(602) 评论(0) 推荐(0) 编辑
[LeetCode] Minimum Window Substring
摘要：This post shares a nice explanation, which is implemented here. The code is rewritten below. 1 class Solution { 2 public: 3 string minWindow(strin... 阅读全文
posted @ 2015-09-08 18:42 jianchao-li 阅读(206) 评论(0) 推荐(0) 编辑
[LeetCode] Valid Sudoku
摘要：This problem is relatively easy. The challenge is how to get a concise code. This post shares a very elegant one which traverses each cell of board on... 阅读全文
posted @ 2015-09-08 17:51 jianchao-li 阅读(226) 评论(0) 推荐(0) 编辑
[LeetCode] Sudoku Solver
摘要：Just don't be scared by this problem :-) It's also very standard backtracking problem. This post shares a very concise code, which is rewritten below ... 阅读全文
posted @ 2015-09-08 17:35 jianchao-li 阅读(219) 评论(0) 推荐(0) 编辑
[LeetCode] First Bad Version
摘要：Just use binary search to find the first bad version.The code is as follows. 1 // Forward declaration of isBadVersion API. 2 bool isBadVersion(int ver... 阅读全文
posted @ 2015-09-07 21:52 jianchao-li 阅读(177) 评论(0) 推荐(0) 编辑
[LeetCode] Find the Celebrity
摘要：Problem Description: Suppose you are at a party with n people (labeled from 0 to n - 1) and among them, there may exist one celebrity. The definition 阅读全文
posted @ 2015-09-06 22:43 jianchao-li 阅读(1276) 评论(0) 推荐(0) 编辑
[LeetCode] Paint Fence
摘要：Problem Description:There is a fence with n posts, each post can be painted with one of the k colors.You have to paint all the posts such that no more... 阅读全文
posted @ 2015-09-05 12:24 jianchao-li 阅读(4185) 评论(0) 推荐(1) 编辑
[LeetCode] H-Index II
摘要：This problem is designed specifically to use binary search. In fact, in H-Index, someone has already used this idea (you may refer to this post :-))Th... 阅读全文
posted @ 2015-09-04 22:19 jianchao-li 阅读(252) 评论(0) 推荐(0) 编辑
[LeetCode] H-Index
摘要：If you've read the Wikipedia article of H-Index, there is already a neat formula there for computing the h-index, which is written below using the not... 阅读全文
posted @ 2015-09-04 22:15 jianchao-li 阅读(398) 评论(0) 推荐(0) 编辑
[LeetCode] Maximal Rectangle
摘要：This link shares a nice solution with explanation using DP. You will be clear of the algorithm after running it on its suggested example:matrix = [[0,... 阅读全文
posted @ 2015-09-02 12:18 jianchao-li 阅读(217) 评论(0) 推荐(0) 编辑
[LeetCode] Reverse Linked List II
摘要：The basic idea is as follows:Create anew_headthat points toheadand use it to locate the immediate node before them-th (notice that it is1-indexed) nod... 阅读全文
posted @ 2015-09-01 23:55 jianchao-li 阅读(154) 评论(0) 推荐(0) 编辑
[LeetCode] Largest Rectangle in Histogram
摘要：This link has a very neat code, which is rewritten below using stacksince thepushandpopoperations of it areO(1)time, while thepop_backandpush_backofve... 阅读全文
posted @ 2015-09-01 21:20 jianchao-li 阅读(205) 评论(0) 推荐(0) 编辑